In fiber-optic communications, wavelength-division multiplexing (WDM) is a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths (i.e., colors) of laser light. Intuitively, a wavelength can be thought of as a particular “color”. Many colors can carry signals for communication and be bundled together and passed down a single fiber, then separated into a receiver to receive the carried signals. This technique can be used for bidirectional communications over one strand of fiber, as well as multiplication of capacity.
Conventional DWDM optical systems applies to mainly static traffic by provisioning the traffic in advance through rigorous optical power management and control. These systems may not be capable of handling dynamic traffic control such as burst mode traffic due to many reasons, among which are the unpredictable optical power at each optical amplifiers resulting in transit noise optical amplifier, large variation of the received optical power and clock phase as well as slow switching time from one wavelength to others, making the dynamic DWDM network may not be feasible in practice. For example, traditional optical burst mode networks may suffer from unpredictable optical at optical amplifiers, resulting transit noise from OA; or a receiver may see burst traffic from different nodes at different time with no signal between bursts, leading to large variation of the signal and clock from burst to burst as well as the needs for long pre-amble; or a slow switching from one wavelength to others may happen in burst mode.
Conventional dense wavelength-division multiplexing (DWDM) optical systems include stacks of optical line-cards and an optical multiplexer (MUX)-demultiplexer (DEMUX)-card. The optical line-cards transmit and receive high-speed modulated DWDM optical signals. The optical MUX-DEMUX card multiplexes all DWDM wavelengths at transmitter side and demultiplexes the DWDM wavelengths at receive side.